Improved Diameter, Velocity, and Temperature Measurements for Char Particles in Drop-Tube Reactors

Abstract

Coal combustion researchers have typically used the average temperature and residence time of a burning particle cloud to determine the high-temperature reactivity of coals and chars. These average values, however, cannot account for particle-to-particle variations or their possible causes. Researchers at Sandia National Laboratories developed a pyrometry technique to simultaneously measure the temperature, velocity, and diameter of individual char particles burning in a transparent-wall flat-flame facility. This work reports two significant advances relative to the optical pyrometry technique. First, pyrometer modifications together with a new analysis technique now permit the particle properties to be measured for smaller/cooler particles